To connect a USB device to a VirtualBox VM requires the proprietary extensions for VirtualBox (which are available at no charge). You may want to expand this answer to explain this, and how to install them.
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Eliah KaganJun 26 '12 at 23:23

I'm using Ubuntu 12.04 and syncing music to my iPhone through Google Play Music. It's working very well. Google Play has an Ubuntu music manager you can download at https://play.google.com/music/listen#manager_pl. Using this application, I uploaded my entire iTunes library (up to 20,000 songs are free). Then I installed the "Melodies" app on my iPhone to stream my music. I like this app because it lets you save songs to your iPhone for offline listening. Tip: Newer iTunes songs (.m4a files) are DRM-free, so they can be easily uploaded to Google Play. Older iTunes songs (.m4p files) have DRM encoding and have to be converted first. To make the conversion, I burned these songs to a CD using iTunes (be sure to check "Include CD Text") and then imported them back into iTunes. There are other options to convert songs, but this was the easiest since I didn't have very many.